An important application in the field of electromobility is the use of battery-charging devices for electric vehicles.
In the charging process of electric vehicles, various parameters must be adjusted by the charging station in order to be able to charge the vehicle battery with a specific energy quantity in a set time period. These parameters are, in particular, charging voltage and charging rate. It is a fundamental fact that these parameters are regulated by a control unit on the vehicle side. For this, a radio unit on the vehicle side is known from U.S. Pat. No. 5,049,802, which sends information about the current charging status of the vehicle battery to the charging station.
The charging of the energy quantity is determined by a meter during the charging process of electric vehicles. This meter is an integrating measuring device with a counter for measuring the electrical work or the electrical energy quantity. Equivalent terms for this are electricity meter, energy meter, energy quantity meter or usage meter.
A meter equipped with a GSM module is known from DE 20 2005 012 949 U1, in order to be able to transmit the meter reading from the meter to a control centre.
Electrical sockets equipped with cash-free advanced payment systems are known from EP 2017582 A1. Among other things, it is recommended that parking meters be equipped with said electrical sockets, so that the battery of an electric vehicle can be charged while parking via the electrical socket installed in the parking meter.
A system for the allocation of energy quantities between individual loads is described in US 2008/0281663 A1. The allocation of the energy quantities is carried out with the goal of preventing peak loads in the electrical power network. Electric vehicles can also be included in the system, wherein the electric vehicle user has the option of adjusting the energy exchange with a mobile device in terms of the set parameters.
In the charging process of electric vehicles, there is, however, an additional problem in that a charging process is not protected from misuse once it has been started. As soon as the electric vehicle is unsupervised, the charging cable can be removed by an unauthorised person and used for a different electric vehicle.
A charge column for electric vehicles is known from GB 2438979, wherein the charging process is started by user identification and wherein the charging cable is mechanically locked in the charge column during the charging process. Such a charge column is therefore mechanically protected from misuse. The disadvantage of such a charge column is once again that proportionally high costs have to be paid for the construction of a comprehensive network of correspondingly arranged charge columns.